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By changing the Stress Goal/Safety Factor, the stiffness of the structure can be influenced as well. Due to uniformly distributed stresses, lower Safety Factors result in stiffer parts at the most lightweight design.
Stresses & Failure Criteria in Combination with the Resolution
The used Stress Goal / Failure Criterion is dependent on the resolution level during the optimisation. The optimisation runs on different resolution levels and switches between them to achieve the best results. The first iterations are calculated on a coarse resolution level. With rising number of iterations, the resolution gets finer. This means that the first iterations calculate much faster than the last iterations but aren’t as detailed as the last. With the increasing resolution, the size of the output data, the calculation time as well as the surface quality increase.
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For further information regarding the stresses and Failure Criteria in the Post Processing, have a look here.